Usage of cellular phone continues to rise. In fact, many individuals and businesses have become or are becoming dependent upon cellular phones, which is promoted in part by special discounts and plans offered by cellular phone service providers for various types of calls and time periods. For instance, due in part to the proliferation of usage by businesses during weekdays, many cellular phone service providers like Cingular™, T-Mobile™, Sprint™ and Verizon™ offer unlimited weekends.
Charges for phone usage are described to some extent in a service contract that a cellular phone user executes typically when purchasing a cellular phone. More specifically, service contracts typically include a monthly charge, time periods in which different rates are charged, locations from which calls can be originated without additional charges, locations to which calls may be placed without additional charges, a number of minutes that are included in the contract for the monthly fee (often referred to as anytime minutes), and other special discounted rates. Special discounts included in service contracts can include unlimited minutes over weekends such as after, e.g., 9:00 pm on Friday through 5:00 pm on Sunday, and unlimited minutes outside certain time periods during weekdays such as after 7:00 pm or 9:00 pm. Furthermore, some service contracts may offer unlimited minutes for calls between cellular phones associated with service contracts from the same cellular phone service provider.
However, in accordance with the service contracts, most provisions a restricted to time periods and/or geographic locations for the cellular phones involved with the calls. Furthermore, most service contracts include clauses that allow provisions of the contracts to be updated or modified in response to changing conditions. For instance, rates will change over time due to lease rates that cellular service providers pay for physical phone lines or data rates over the Internet.
Geographic boundaries for cellular phone providers change over time due to the availability of and contracts with cellular phone servers such as mobile telephone switching offices (MTSOs). An MTSO is a central switch that controls the entire operation of a cellular system. The MTSO is a sophisticated computer that monitors all cellular calls, tracks the location of all cellular-equipped vehicles traveling in the system, arranges handoffs, keeps track of billing information, etc. In many cities, there may be only one MTSO to handle all cellular phone calls within the city.
Each cellular phone service provider, or carrier, is assigned a unique identification number by the Federal Communications Commission (FCC) called a system identification code (SID) and each cellular phone includes the SID, e.g., on a subscriber identity module (SIM) to associate the phone with a carrier and a service contract. When a cellular phone is powered, the cellular phone looks for the frequency of a previously found MTSO and/or searches frequencies for an MTSO. Upon finding the MTSO, the cellular phone transmits the SID and the subscriber identity to the MTSO and the MTSO verifies the subscriber identity with the carrier. Upon verification, the user may send or receive calls via the MTSO.
While the average per minute charges seem to be dropping, the service contacts for cellular phone use are so complicated and subject to change that cellular phone users typically cannot figure out whether or not they will be charged for a particular call. For instance, there is no indication whether the cellular phone user will be charged is within a free time period, a geographic location that is free from additional charges, or that the user still has some remaining anytime minutes. Currently, many cellular phones indicate that the phone is “Roaming” when the phone is registered in a geographic location that is not the designated “home” location for purposes of the service contract, but “Roaming” does not actually indicate whether or not additional charges apply to a call because many service contracts include some “Roaming” areas free of additional charges.
Many cell phone carriers also offer unlimited mobile-to-mobile calling to members of the same carrier; however, there is no easy way for the end user to identify the carrier of the incoming call or of the phone that is being called without actually asking the person at the other end after initiating the call. Without this identification, the user has no way of knowing whether the user can take advantage of the unlimited mobile-to-mobile calling feature. For example, a user may not want to use anytime minutes to answer a call from an unknown or blocked caller but the user may be willing to answer if the call is free of any additional charges.